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          数据结构中的单链表（Java语言）
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        <p>Java语言实现单链表</p>
<a id="more"></a>

<h2 id="定义"><a href="#定义" class="headerlink" title="定义"></a>定义</h2><p><strong>单向链表</strong>（又名单链表、线性链表）是<a href="https://zh.wikipedia.org/wiki/%E9%93%BE%E8%A1%A8" target="_blank" rel="noopener">链表</a>的一种，其特点是链表的链接方向是单向的，对链表的访问要通过从头部开始，依序往下读取。</p>
<p>一个单向链表的节点被分成两个部分。第一个部分保存或者显示关于节点的信息，第二个部分存储下一个节点的地址。单向链表只可向一个方向遍历。</p>
<h2 id="实现"><a href="#实现" class="headerlink" title="实现"></a>实现</h2><p>由于单链表是线性结构的一种，我们可以令其继承上次写的MyList接口</p>
<figure class="highlight java"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br><span class="line">44</span><br><span class="line">45</span><br><span class="line">46</span><br><span class="line">47</span><br><span class="line">48</span><br><span class="line">49</span><br><span class="line">50</span><br><span class="line">51</span><br><span class="line">52</span><br><span class="line">53</span><br><span class="line">54</span><br><span class="line">55</span><br><span class="line">56</span><br><span class="line">57</span><br><span class="line">58</span><br><span class="line">59</span><br><span class="line">60</span><br><span class="line">61</span><br><span class="line">62</span><br><span class="line">63</span><br><span class="line">64</span><br><span class="line">65</span><br><span class="line">66</span><br><span class="line">67</span><br><span class="line">68</span><br><span class="line">69</span><br><span class="line">70</span><br><span class="line">71</span><br><span class="line">72</span><br><span class="line">73</span><br><span class="line">74</span><br><span class="line">75</span><br><span class="line">76</span><br><span class="line">77</span><br><span class="line">78</span><br><span class="line">79</span><br><span class="line">80</span><br><span class="line">81</span><br><span class="line">82</span><br><span class="line">83</span><br><span class="line">84</span><br><span class="line">85</span><br><span class="line">86</span><br><span class="line">87</span><br><span class="line">88</span><br><span class="line">89</span><br><span class="line">90</span><br><span class="line">91</span><br><span class="line">92</span><br><span class="line">93</span><br><span class="line">94</span><br><span class="line">95</span><br><span class="line">96</span><br><span class="line">97</span><br><span class="line">98</span><br><span class="line">99</span><br><span class="line">100</span><br><span class="line">101</span><br><span class="line">102</span><br><span class="line">103</span><br><span class="line">104</span><br><span class="line">105</span><br><span class="line">106</span><br><span class="line">107</span><br><span class="line">108</span><br><span class="line">109</span><br><span class="line">110</span><br><span class="line">111</span><br><span class="line">112</span><br><span class="line">113</span><br><span class="line">114</span><br><span class="line">115</span><br><span class="line">116</span><br><span class="line">117</span><br><span class="line">118</span><br><span class="line">119</span><br><span class="line">120</span><br><span class="line">121</span><br><span class="line">122</span><br><span class="line">123</span><br><span class="line">124</span><br><span class="line">125</span><br><span class="line">126</span><br><span class="line">127</span><br><span class="line">128</span><br><span class="line">129</span><br><span class="line">130</span><br><span class="line">131</span><br><span class="line">132</span><br><span class="line">133</span><br><span class="line">134</span><br><span class="line">135</span><br><span class="line">136</span><br><span class="line">137</span><br><span class="line">138</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">public</span> <span class="class"><span class="keyword">class</span> <span class="title">SingleLinkedList</span> <span class="keyword">implements</span> <span class="title">MyList</span> </span>&#123;</span><br><span class="line">    <span class="keyword">private</span> ListNode first;     <span class="comment">//声明头节点</span></span><br><span class="line">    <span class="keyword">private</span> ListNode last;      <span class="comment">//声明尾节点</span></span><br><span class="line">    <span class="keyword">private</span> <span class="keyword">int</span> size = <span class="number">0</span>;       <span class="comment">//确定链表的大小</span></span><br><span class="line">    <span class="keyword">private</span> ListNode p;     <span class="comment">//定义指针p</span></span><br><span class="line"></span><br><span class="line">    <span class="comment">//往链表后增加元素，注意边界值，第一个元素的添加</span></span><br><span class="line">    <span class="meta">@Override</span></span><br><span class="line">    <span class="function"><span class="keyword">public</span> <span class="keyword">void</span> <span class="title">add</span><span class="params">(Object element)</span> </span>&#123;</span><br><span class="line">        <span class="keyword">if</span> (first == <span class="keyword">null</span>) &#123;</span><br><span class="line">            first = <span class="keyword">new</span> ListNode(element);</span><br><span class="line">            last = first;</span><br><span class="line">        &#125; <span class="keyword">else</span> &#123;</span><br><span class="line">            last.next = <span class="keyword">new</span> ListNode(element);</span><br><span class="line">            last = last.next;</span><br><span class="line">        &#125;</span><br><span class="line">        size++;</span><br><span class="line">    &#125;</span><br><span class="line"></span><br><span class="line">    <span class="comment">//删除链表中的某个元素，调用其他方法</span></span><br><span class="line">    <span class="meta">@Override</span></span><br><span class="line">    <span class="function"><span class="keyword">public</span> <span class="keyword">void</span> <span class="title">delete</span><span class="params">(Object element)</span> </span>&#123;</span><br><span class="line">        <span class="keyword">int</span> res = contains(element);</span><br><span class="line">        delete(res);</span><br><span class="line">    &#125;</span><br><span class="line"></span><br><span class="line">    <span class="comment">//删除元素，注意边界值，第一个元素和最后一个元素。这个方法值得思考</span></span><br><span class="line">    <span class="comment">//双节点的思想，如果没有size，那么每次删除都要遍历</span></span><br><span class="line">    <span class="comment">//删除可以考虑将其进行简化</span></span><br><span class="line">    <span class="meta">@Override</span></span><br><span class="line">    <span class="function"><span class="keyword">public</span> <span class="keyword">void</span> <span class="title">delete</span><span class="params">(<span class="keyword">int</span> index)</span> </span>&#123;</span><br><span class="line">        <span class="keyword">if</span> (index &lt; <span class="number">0</span> || index &gt;= size) &#123;		<span class="comment">//考虑范围</span></span><br><span class="line">            <span class="keyword">return</span>;</span><br><span class="line">        &#125; <span class="keyword">else</span> <span class="keyword">if</span> (index == <span class="number">0</span>) &#123;		<span class="comment">//考虑首节点</span></span><br><span class="line">            first = first.next;</span><br><span class="line">        &#125; <span class="keyword">else</span> <span class="keyword">if</span> (index == size - <span class="number">1</span>) &#123;		<span class="comment">//考虑尾节点</span></span><br><span class="line">           p = first;</span><br><span class="line">            ListNode prep = p;</span><br><span class="line">            <span class="keyword">int</span> i = <span class="number">0</span>;</span><br><span class="line">            <span class="keyword">while</span> (i &lt; size - <span class="number">1</span>)&#123;</span><br><span class="line">                i++;</span><br><span class="line">                prep = p;</span><br><span class="line">                p = p.next;</span><br><span class="line">            &#125;</span><br><span class="line">            prep.next = <span class="keyword">null</span>;</span><br><span class="line">            last = p;</span><br><span class="line">        &#125; <span class="keyword">else</span> &#123;		<span class="comment">//考虑中间节点</span></span><br><span class="line">            p = first;</span><br><span class="line">            ListNode prep = p;</span><br><span class="line">            <span class="keyword">int</span> i = <span class="number">0</span>;</span><br><span class="line">            <span class="keyword">while</span> (i &lt; index) &#123;</span><br><span class="line">                i++;</span><br><span class="line">                prep = p;</span><br><span class="line">                p = p.next;</span><br><span class="line">            &#125;</span><br><span class="line">            prep.next = p.next;</span><br><span class="line">        &#125;</span><br><span class="line">        size--;</span><br><span class="line">    &#125;</span><br><span class="line"></span><br><span class="line">    <span class="comment">//修改指定索引的值</span></span><br><span class="line">    <span class="meta">@Override</span></span><br><span class="line">    <span class="function"><span class="keyword">public</span> <span class="keyword">void</span> <span class="title">update</span><span class="params">(<span class="keyword">int</span> index, Object newElement)</span> </span>&#123;</span><br><span class="line">        <span class="keyword">if</span> (index &lt; <span class="number">0</span> || index &gt; size)</span><br><span class="line">            <span class="keyword">return</span>;</span><br><span class="line">        <span class="keyword">int</span> i = <span class="number">0</span>;</span><br><span class="line">        p = first;</span><br><span class="line">        <span class="keyword">while</span> (i &lt; index) &#123;</span><br><span class="line">            i++;</span><br><span class="line">            p = p.next;</span><br><span class="line">        &#125;</span><br><span class="line">        p.data = newElement;</span><br><span class="line">    &#125;</span><br><span class="line"></span><br><span class="line">    <span class="comment">//查询指定索引上的元素</span></span><br><span class="line">    <span class="meta">@Override</span></span><br><span class="line">    <span class="function"><span class="keyword">public</span> Object <span class="title">at</span><span class="params">(<span class="keyword">int</span> index)</span> </span>&#123;</span><br><span class="line">        <span class="keyword">if</span> (index &lt; <span class="number">0</span> || index &gt;= size)</span><br><span class="line">            <span class="keyword">return</span> <span class="keyword">null</span>;</span><br><span class="line">        p = first;</span><br><span class="line">        <span class="keyword">int</span> i = <span class="number">0</span>;</span><br><span class="line">        <span class="keyword">while</span> (i &lt; index) &#123;</span><br><span class="line">            p = p.next;</span><br><span class="line">            i++;</span><br><span class="line">        &#125;</span><br><span class="line">        <span class="keyword">return</span> p.data;</span><br><span class="line">    &#125;</span><br><span class="line"></span><br><span class="line">    <span class="comment">//查询包含该元素的索引</span></span><br><span class="line">    <span class="meta">@Override</span></span><br><span class="line">    <span class="function"><span class="keyword">public</span> <span class="keyword">int</span> <span class="title">contains</span><span class="params">(Object element)</span> </span>&#123;</span><br><span class="line">        p = first;</span><br><span class="line">        <span class="keyword">int</span> index = <span class="number">0</span>;</span><br><span class="line">        <span class="keyword">while</span> (p != <span class="keyword">null</span>) &#123;</span><br><span class="line">            <span class="keyword">if</span> (element.equals(p.data)) &#123;</span><br><span class="line">                <span class="keyword">return</span> index;</span><br><span class="line">            &#125;</span><br><span class="line">            p = p.next;</span><br><span class="line">            index++;</span><br><span class="line">        &#125;</span><br><span class="line">        <span class="keyword">return</span> -<span class="number">1</span>;</span><br><span class="line">    &#125;</span><br><span class="line"></span><br><span class="line">    <span class="comment">//往指定索引后添加元素</span></span><br><span class="line">    <span class="function"><span class="keyword">public</span> <span class="keyword">void</span> <span class="title">insert</span><span class="params">(<span class="keyword">int</span> index,Object element)</span></span>&#123;</span><br><span class="line">        <span class="keyword">if</span>(index &lt; <span class="number">0</span> || index &gt;= size)</span><br><span class="line">            <span class="keyword">return</span>;</span><br><span class="line">        p = first;</span><br><span class="line">        <span class="keyword">int</span> i = <span class="number">0</span>;</span><br><span class="line">        <span class="keyword">while</span> (i &lt; index)&#123;</span><br><span class="line">            i++;</span><br><span class="line">            p = p.next;</span><br><span class="line">        &#125;</span><br><span class="line">        <span class="keyword">if</span>(p.next == <span class="keyword">null</span>)&#123;</span><br><span class="line">            add(element);</span><br><span class="line">        &#125;<span class="keyword">else</span> &#123;</span><br><span class="line">            ListNode temp = p.next;</span><br><span class="line">            p.next = <span class="keyword">new</span> ListNode(element);</span><br><span class="line">            p.next.next = temp;</span><br><span class="line">        &#125;</span><br><span class="line">    &#125;</span><br><span class="line"></span><br><span class="line">    <span class="comment">//重写toString()方法，遍历方式与列表注意区分</span></span><br><span class="line">    <span class="meta">@Override</span></span><br><span class="line">    <span class="function"><span class="keyword">public</span> String <span class="title">toString</span><span class="params">()</span> </span>&#123;</span><br><span class="line">        StringBuilder sb = <span class="keyword">new</span> StringBuilder(<span class="string">"["</span>);</span><br><span class="line">        p = first;</span><br><span class="line">        <span class="keyword">while</span> (p != <span class="keyword">null</span>) &#123;</span><br><span class="line">            sb.append(p.data);</span><br><span class="line">            <span class="keyword">if</span> (p.next != <span class="keyword">null</span>) &#123;</span><br><span class="line">                sb.append(<span class="string">","</span>);</span><br><span class="line">            &#125;</span><br><span class="line">            p = p.next;</span><br><span class="line">        &#125;</span><br><span class="line">        sb.append(<span class="string">"]"</span>);</span><br><span class="line">        <span class="keyword">return</span> sb.toString();</span><br><span class="line">    &#125;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>



<h3 id="要点"><a href="#要点" class="headerlink" title="要点"></a>要点</h3><h3 id="指针的移动"><a href="#指针的移动" class="headerlink" title="指针的移动"></a>指针的移动</h3><p>p为定义的指针，将首节点赋予给它，然后通过while语句将其逐个往下遍历</p>
<figure class="highlight java"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br></pre></td><td class="code"><pre><span class="line"> <span class="comment">//查询包含该元素的索引</span></span><br><span class="line"><span class="meta">@Override</span></span><br><span class="line"><span class="function"><span class="keyword">public</span> <span class="keyword">int</span> <span class="title">contains</span><span class="params">(Object element)</span> </span>&#123;</span><br><span class="line">    p = first;				<span class="comment">//将首节点赋予给指针p</span></span><br><span class="line">    <span class="keyword">int</span> index = <span class="number">0</span>;</span><br><span class="line">    <span class="keyword">while</span> (p != <span class="keyword">null</span>) &#123;</span><br><span class="line">        <span class="keyword">if</span> (element.equals(p.data)) &#123;		<span class="comment">//判断该节点的元素是否与传入的一致</span></span><br><span class="line">            <span class="keyword">return</span> index;</span><br><span class="line">        &#125;</span><br><span class="line">        p = p.next;			<span class="comment">//指针移到下一个元素</span></span><br><span class="line">        index++;			<span class="comment">//计数器加一</span></span><br><span class="line">    &#125;</span><br><span class="line">    <span class="keyword">return</span> -<span class="number">1</span>;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<h3 id="预指针的使用"><a href="#预指针的使用" class="headerlink" title="预指针的使用"></a>预指针的使用</h3><figure class="highlight java"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br></pre></td><td class="code"><pre><span class="line"> p = first;</span><br><span class="line">ListNode prep = p;</span><br><span class="line"><span class="keyword">int</span> i = <span class="number">0</span>;</span><br><span class="line"><span class="keyword">while</span> (i &lt; size - <span class="number">1</span>)&#123;</span><br><span class="line">    i++;</span><br><span class="line">    prep = p;</span><br><span class="line">    p = p.next;</span><br><span class="line">&#125;</span><br><span class="line">prep.next = <span class="keyword">null</span>;</span><br><span class="line">last = p;</span><br></pre></td></tr></table></figure>

<p><img src="/2019/11/10/%E5%8D%95%E9%93%BE%E8%A1%A8/C:%5CUsers%5CFWJ%5CAppData%5CRoaming%5CTypora%5Ctypora-user-images%5C1573374795390.png" alt="1573374795390"></p>
<p>当删除元素时，我们需要将要删除的结点的前一个结点与后一个结点建立联系，但是由于我们只能从一个结点获取它的下一个结点，所以我们定义一个“预指针”，这样就可以同时获得要删除结点的前一个结点和后一个结点。</p>
<p>设置要删除节点前一个节点的next为后一个节点。这样在下一次遍历的时候跳过了要删除的节点，实现了我们删除该节点的目的。</p>
<h3 id="新增了插入，在指定索引后添加元素"><a href="#新增了插入，在指定索引后添加元素" class="headerlink" title="新增了插入，在指定索引后添加元素"></a>新增了插入，在指定索引后添加元素</h3><figure class="highlight java"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br></pre></td><td class="code"><pre><span class="line"><span class="function"><span class="keyword">public</span> <span class="keyword">void</span> <span class="title">insert</span><span class="params">(<span class="keyword">int</span> index, Object element)</span> </span>&#123;</span><br><span class="line">    <span class="keyword">if</span> (index &lt; <span class="number">0</span> || index &gt;= size)</span><br><span class="line">        <span class="keyword">return</span>;</span><br><span class="line">    p = first;</span><br><span class="line">    <span class="keyword">int</span> i = <span class="number">0</span>;</span><br><span class="line">    <span class="keyword">while</span> (i &lt; index) &#123;</span><br><span class="line">        i++;</span><br><span class="line">        p = p.next;</span><br><span class="line">    &#125;</span><br><span class="line">    <span class="keyword">if</span> (p.next == <span class="keyword">null</span>) &#123;</span><br><span class="line">        add(element);</span><br><span class="line">    &#125; <span class="keyword">else</span> &#123;</span><br><span class="line">        ListNode temp = p.next;</span><br><span class="line">        p.next = <span class="keyword">new</span> ListNode(element);</span><br><span class="line">        p.next.next = temp;</span><br><span class="line">    &#125;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<p>​    思考：在列表中插入一个数据该怎么做？</p>
<p>​            找到对应的元素，之后的所有元素向后一位，在对应元素的后面插入元素</p>
<h3 id="测试"><a href="#测试" class="headerlink" title="测试"></a>测试</h3><p>测试时要重视测试边界。边界最容易出问题</p>
<figure class="highlight java"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">public</span> <span class="class"><span class="keyword">class</span> <span class="title">SingleLinkedListTest</span> </span>&#123;</span><br><span class="line">    <span class="keyword">private</span> <span class="keyword">static</span> SingleLinkedList sl = <span class="keyword">new</span> SingleLinkedList();</span><br><span class="line">    <span class="keyword">static</span> &#123;</span><br><span class="line">        sl.add(<span class="string">"1"</span>);</span><br><span class="line">        sl.add(<span class="string">"2"</span>);</span><br><span class="line">        sl.add(<span class="string">"3"</span>);</span><br><span class="line">        sl.add(<span class="string">"4"</span>);</span><br><span class="line">    &#125;</span><br><span class="line">    </span><br><span class="line">    <span class="meta">@Test</span></span><br><span class="line">    <span class="function"><span class="keyword">public</span> <span class="keyword">void</span> <span class="title">add</span><span class="params">()</span> </span>&#123;</span><br><span class="line">        sl.add(<span class="string">"5"</span>);</span><br><span class="line">        Assertions.assertThat(sl.toString()).isEqualTo(<span class="string">"[1,2,3,4,5]"</span>);</span><br><span class="line">    &#125;</span><br><span class="line"></span><br><span class="line">    <span class="meta">@Test</span></span><br><span class="line">    <span class="function"><span class="keyword">public</span> <span class="keyword">void</span> <span class="title">delete</span><span class="params">()</span> </span>&#123;</span><br><span class="line">        sl.delete(<span class="string">"4"</span>);</span><br><span class="line">        Assertions.assertThat(sl.toString()).isEqualTo(<span class="string">"[1,2,3]"</span>);</span><br><span class="line">    &#125;</span><br><span class="line"></span><br><span class="line">    <span class="meta">@Test</span></span><br><span class="line">    <span class="function"><span class="keyword">public</span> <span class="keyword">void</span> <span class="title">delete1</span><span class="params">()</span> </span>&#123;</span><br><span class="line">        sl.delete(<span class="number">3</span>);</span><br><span class="line">        Assertions.assertThat(sl.toString()).isEqualTo(<span class="string">"[1,2,3]"</span>);</span><br><span class="line">    &#125;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
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        /* Date.UTC() -- 返回date对象距世界标准时间(UTC)1970年1月1日午夜之间的毫秒数(时间戳)
        year - 作为date对象的年份，为4位年份值
        month - 0-11之间的整数，做为date对象的月份
        day - 1-31之间的整数，做为date对象的天数
        hours - 0(午夜24点)-23之间的整数，做为date对象的小时数
        minutes - 0-59之间的整数，做为date对象的分钟数
        seconds - 0-59之间的整数，做为date对象的秒数
        microseconds - 0-999之间的整数，做为date对象的毫秒数 */
        var t1 = Date.UTC(2019, 11, 7, 17, 50, 00); //北京时间2018-2-13 00:00:00
        var t2 = Date.UTC(todayYear, todayMonth, todayDate, todayHour, todayMinute, todaySecond);
        var diff = t2 - t1;
        var diffYears = Math.floor(diff / years);
        var diffDays = Math.floor((diff / days) - diffYears * 365);
        var diffHours = Math.floor((diff - (diffYears * 365 + diffDays) * days) / hours);
        var diffMinutes = Math.floor((diff - (diffYears * 365 + diffDays) * days - diffHours * hours) / minutes);
        var diffSeconds = Math.floor((diff - (diffYears * 365 + diffDays) * days - diffHours * hours - diffMinutes * minutes) / seconds);
        document.getElementById("sitetime").innerHTML = "本站已运行 " +diffYears+" 年 "+diffDays + " 天 " + diffHours + " 小时 " + diffMinutes + " 分钟 " + diffSeconds + " 秒";
    }/*因为建站时间还没有一年，就将之注释掉了。需要的可以取消*/
    siteTime();
</script>


        












        
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